Hypertonia and Tonicity

Hypertonia noun - (of muscular tissue) the state of being hypertonic.

Tonicity and hypertonia are semantically related. In some cases you can use "Tonicity" instead a noun "Hypertonia".

Tonicity noun - The elastic tension of living muscles, arteries, etc. that facilitate response to stimuli.

Hypertonia and tonicity are semantically related. Sometimes you can replace term "Hypertonia" with "Tonicity", this nouns are similar.